Method and apparatus for interrupting electrical circuits



Apnl 5, 1927 w, DUBILIER METHOD AND APPARATUS FOR INTERHUPTING ELECTRICAL CIRCUITS f Filed Nov. 23, 1922 INVENTOR ATTORNEY Patented Apr. 5, 1927.

di UNITED STATES WILLIAM DUBILIEB,

, 1,6231531 PATENT OFFICE.

F NEW YORK, N. Y.

mHOD AIDU)v APPARATUS FOB. ITRBUPTING' ELECTRICAL CIRCUITS.

Application led November 2B, 1922.` Seria lo. 608,798.

My invention relates to a method of` and apparatus being provided with heat radiatmg means.

Other objects will hereinafter more fully a r. w

p or the sake of illustration, I have applied my invention to a well known form of circuit mterrupter, as illustrated. in thev accompanying drawing, in which Fig. l is a kside elevation of a circuit interrupter constructed in accordance' with my invention .and illustrating the method of operation l claim as new.

Eig. 2 is a view of a modified portion the mechanism shown inl Fig. l1.

ig. 3 is a view showing the contacts Fig. l the open position. v l

Like figures of reference denote the same parts wherever they are shown.

Reiferriung to the drawing, the device here shown comprises an insulating panel l, a. main stationary Contact member 2, `a mov able w5o-operating contact member 3 and a supporting arm 4 forthe member 3. The

arm 4 is operated in the usual manner by means of a handle 5, and. released by any suitable overload device such as the usual coil employed for this purpose and indin cated at .6. As the construction and opera'- tion of the movable member of such circuit breakers may bevaried within wide limits and many such arrangements are known, 1 do not describe the same.

Carried; upon the insulating panel l is an auxiliary contact member 7 provided with one or more heat radiating fins 8. This member may be connected "to the main sta'- tionary contact member n2 by means of the connection 9 and the supportin bolt and terminal 10 for the member 7. he contact surface of the member 7 is preferably and usually of copper. f

The nanel 1 also carries a support 11, upon which is supported an auxiliary contact 12, which ma be equipped with heat radiating fins 13. his contact 12 is supported upon a resilient spring 14 provided with suitable adjusting means such as a screw 15 whereby the tension of the spring 14 may be adjusted, thus determining the extentof the am gap 16 that may occurwhen terminals 7 and 12 are separated,` as shown in Fig. 3.

The spring 14 also carries a suitable arcing contact, such as the carbon member 17,

which is adapted to engage asimilar member 18, preferably of carbon, mounted in any suitable manner upon the arm 4.

In cases where it appears desirable,l the arrangement used in Fig. 2 may be employed, in which a supplemental contact 19 equipped with heat radiating fins 20, is employed and included serially in the circuit. 1D. this case, the contact surfaces on both sides of the auX- iliary spring 21 are of copper or other suitable material. An auxiliary adjusting screw 22 is provided for adjusting the au' gap between 7 and 19 when the circuit breaker is open, this screw cooperating with a support 25.

.lfihen the arrangement shown in Fig. 2 is employed, it is obvious that there are two i the quenched spark gap/indicated by nu@ meral 16..

lf the arrangement shown in Fig. 2 is employed, then a second quenched gap at 27 will exist between the supplemental contact 19 and the opposed face of 7, as will be observed by tracing the circuit from terminal 10 to the face of contact 7 engaging 19, throng? contact 19 to the face of contact 12, througi 12 to arcing contact 17, and tothe engagin face of 18 to arm 4, to bolt 24. The quench gaps are at 26 and v27 when the contacts are separated.

The foregoing description of a common forni of circuit breaker will serve to illustrate myinvention, which it will be seen consists broadly of the method of introducing a quenched spark gap, or gaps, in series with the usual contact members, wherethe circuit is usually broken.

I do not describe in detail the function of the quenched gap. The action of such gaps in electrical circuits are well understood, but I do not wish to point out that by mounting the auxiliary' contacts, such as 12 and 19, upon a resilient support or supports, and having thesurfaces of these contacts ot sufficient dimensions to readily radiate heat, that when the breaker arm or otherimember releases the contacts trom engagement, that not only does the small gap forming the quenched gap, and usually not over .010 occur, but by reason of the action of the springs 14, 21., and the supplemental springs 27 and 28 employed in connection with adjusting screws 15, Q2, a vibratory action ot of the supplemental contacts 12, 19 will take place. This vibratory action causes the auxiliary contacts to pass many times through the critical point, producing the well known are quenching effect. The arcing distance ot' these gaps is so small that the heat gen erated is rapidly conducted away trom the centerof the arc.

It is obvious that this method ot circuit interruption may be applied to all classes of devices in which it is necessary to interrupt an electrical circuit, and where it is desirable at the time of said interruption that the arcing and heat generated shall be reduced to a minimum, and that once this principle or method having been disclosed, that mechanisms for utilizing the same in connection with induction coil interrupters, circuit breakers, elevator motor controls, manual and motor operated switches, and in fact all forms of circuit `interrupting apparatus, are mere modifications which come within the scope of the appended claims.

' ber, 1922.

Heretofore, it has not been practical to use metal contacts on many forms of' interrupters on account of the contacts pitting. In some cases, the employment of carbon arcing contacts 17 and 18, as used in the illustrative form of interrupter just described, is not desirable. My invention makes it possible to eliminate such carbon contacts in many cases, and enables these contacts to be made of metal, and thereby carry all of the current flowing in. the circuit, sometimes eliminating thc use of the usual main contacts 2 and 3.

The advantage of circuit interrupter mechanism in which the lite ot' the contacts is prolonged and in which means is provided for radiating the heat generated at the break,

is obvious.

I claim as my invention:

1. A circuit interrupter comprising co operating contact members, operating mechanism therefor, and vibrator-y arc quenching' means cooperating therewith.

2. A circuit interrupting device comprising circuit interrupter mechanism, and a vibratory arc quenching member operated by said' mechanism, and included serially in circuit therewith.

3. A. circuit interrupting device comprising a switch, vibratory arc quenching means in series therewith, and means for conducting away the heat of the arc.

4. A circuit interrupting device comprising cooperating members having refractory conducting surfaces adapted to torm a gap, a member cooperating with said irst members to produce a quenched gap in series therewith, and metallic cooperating surfaces between one of said first members and said second member.

In testimony whereof, I have hereunto subscribed my name this 15th day of Novem- WILLIAM DUBILIER; 

